Recently, the rapid advances of imaging devices have accelerated the development of various photographing devices, such as cameras, or camcorders, which adopt image sensors. The photographing devices are widely used since it is convenient for images to be photographed, stored, and reproduced in and from a recording medium any time. Therefore, user demands for performance and functions of the photographing devices are gradually increasing, and there is a growing trend towards photographing devices of high performance and various functions as well as small, light, and low-power consuming photographing devices.
The photographing devices basically adopt automatic functions, such as an auto-focus (AF) function and an auto-exposure (AE) function.